dupeGuru and moneyGuru run very well on Linux, but Linux has so many distributions that it's hard to keep up. So that why I only create builds for Ubuntu. There are other marginally supported distributions, but details about them are a bit verbose, so they have their own page.
Windows is not supported any more because dupeGuru and moneyGuru lack a Windows maintainer. If you're stuck on Windows, you'll have to use older versions of dupeGuru and moneyGuru.
Looking for OS X Tiger, Leopard, Snow Leopard or for Windows builds? These are not supported any more, but if you don't mind using older versions of dupeGuru and moneyGuru, those downloads are still available.
At the bottom of each application page, there's a section "Old versions" where there are links to older versions for older OSes. It's a section that's easy to miss if you're not looking carefully. Scroll to the bottom of the application's page, it's there.